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STRUCTURAL DETAILING 147▲ 7.29 Stratford Regional Station, London, England, WilkinsonEyre, 1999. Curved frames spring from cast-steel bases.▲ 7.30 Lyons School of Architecture, France, Jourda etPerraudin, 1988. A cast-steel shoe expresses the compressionload-path.but its anthropomorphic forms create an aesthetic of movement andlightness.At another railway station, the Stratford Regional Station, London,structural actions similarly inspire expressive detailing (Fig. 7.29).Although the focus here is upon just one detail, the base-connection ofthe portal frames, other details, such as how the primary curved framestaper to points where they are propped, equally express structuralaction. Each frame base-connection joins the frame rigidly to a concretesubstructure. This base rigidity helps the frame resist gravity and lateralloads, and minimizes its depth.High-strength bars tension the base-plates down to the concrete viacast-steel bases. Rather than adopt usual construction practice wherebya column base-plate connects directly to a concrete foundation by verticalbolts whose shafts are concealed, this detailing expresses how thebase-plate is clamped down. Not only are the bolt shafts visible, buttheir inclination aligns them parallel to the lines of stress within theframe member. The shaping and roundness of the base exemplifiesthe ‘adapting’ of form, spoken of by Anderson previously. The baseexpresses and elaborates how tensions from the embedded bars compressthe base-plate against the concrete, and how this compressionstress that acts upon the base is dispersed uniformly at the steel-baseto concrete interface.Connections of timber members at the Lyons School of Architecture,Lyons, present a more overt example of elaborating structural detailsfor the sake of improved expression (see Fig. 6.17). Delicate cast-steelshoes provide the transition detail at both ends of the inclined strutsand vertical columns (Fig. 7.30). The elaboration of these details takes